Here is a bytes type.  It's very minimal but it's a start.
diff --git a/Include/Python.h b/Include/Python.h
index 161c838..fffc688 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -78,6 +78,7 @@
 
 #include "pydebug.h"
 
+#include "bytesobject.h"
 #include "unicodeobject.h"
 #include "intobject.h"
 #include "boolobject.h"